I have never owned nor used an airsoft pistol, but a good friend of mine who shoots steel matches with me recommended looking at getting one for cheap trigger time, and he recommended the KWA brand. I have been recklessly eyeballing one of the PTP 1911's (the Mk. III I think), but one thing I would like to know is if KWA makes an arched main spring housing, or if a genuine article main spring housing can be used in its stead. My primary conceal carry handgun is a Springfield Armory Loaded model 1911, with the arch main spring housing, so if I were to pick up a KWA Mk. III, I would want it to match my Loaded model.

I wouldn't be surprised if a arched MSH fit and I don't know for sure but I'm a M1911-guy. I've not tried it with my Mark I. (Now that I've had the Mark I for a while I'm sorry I didn't get the Mark II.)

KWA is reported to be releasing a WW2-vintage M1911A1 which should contain the arched MSH. I'd wait for it to see.

I swore for years I needed the arched mainspring housing in the M1911 and retrofitted it to all my M1911s. I'm down to 4 or 5 M1911s (yes, it's a disease but I'm recovering slowly...) with a mix of arched, straight, and bob-tailed MSHs and it doesn't seem to matter. I normally carry my Ed Brown Kobra Carry or Colt Commander and use a Government Model for full caliber training and practice. And the Mark I in the backyard, garage, and basement.

As for your Springfield Loaded (a wonderful pistol, by the way, I had the full size model for several years), have you eliminated the lock? Takes only a couple of parts (plunger and plunger pin and a standard mainspring). An Ed Brown 19# mainspring will dramatically improve the trigger. You can reuse your arched MSH or fit any one of dozens of others. Replacing the (stupid) full length recoil spring guide is also recommended. I'm trying to get rid of this in my KWA Mark I.

A M1911 mainspring housing (MSH) will not fit in the KWA Mark Series. It may be possible to modify a M1911 MSH with quite a bit of work. Here's some photos of my attempts yesterday.

Photo 1. Standard KWA MSH:

Photo 2. Attempt to put a M1911 MSH in the pistol. This is as far as it will go.

Photo 3. Here's why it stops. Note the shape of the MSH at the bottom end in the 48, 69, 50 area of the Beretta mat :

Photo 4. Differences between the two MSHs. Note the area along what is the the forward edge of the MSH is much thinner in the KWA (top) version.

I tried several real M1911 MSHs with identical results. I attempted to modify a plastic, arched MSH to fit with only partial success. Requires more contouring to fit and secure the sear spring properly. (I'll drop this in an envelope for you if you want to play with it more than I did. PM or email me.)

BEWARE: The KWA pistol closely mimics the M1911 internally but not exactly! There are several extra parts that are positioned differently and the vital and nearly microscopic impact pin (#60) will fall out unless you take precautions. The pistol will not function without this part. To change the MSH in either the KWA or cartridge models with the least hassle follow these steps.

1. Unload and clear the pistol.
2. Remove the slide.
3. (KWA Only.) Insert an unloaded magazine. No BBs. No gas. This is vital and a fail safe to secure several small parts in the frame of the airsoft pistol should something go wrong -- especially if you ignore the next step!
4. Tie or rubber band the grip safety tightly in the forward position. This keeps the sear spring in the proper place when you remove the MSH. Failure to do this step will cause the sear spring to come out of proper position and require removal of the grip safety to reposition it. See note later.
5. Push out the MSH pin from left to right. Takes little effort on the KWA.
6. Remove/replace the MSH. Do not mess with the sear spring. Do not remove the string or rubber bands until the new MSH is pinned in place!

Note: If you remove the MSH but failed to secure the grip safety (step 4) the sear spring will be loose and you will have to completely remove the frame and grip safeties to reposition it. The lil' frame safety detents and spring can leap out and be lost. If you also failed to place an unloaded magazine in the KWA pistol (step 3) there will be several vital parts out of position in the frame and the tiny Impact Pin (#60) will probably fall out with a good chance of being lost. Getting those parts back in position is fairly easy (if you haven't lost the impact pin) but why risk it? Ignore steps 3 and 4 (above) at your peril with the KWA. No big deal with the real M1911.

As I noted earlier: "I swore for years I needed the arched mainspring housing in the M1911 and retrofitted it to all my M1911s. I'm down to 4 or 5 M1911s (yes, it's a disease but I'm recovering slowly...) with a mix of arched, straight, and bob-tailed MSHs and it doesn't seem to matter. I normally carry my Ed Brown Kobra Carry or Colt Commander and use a Government Model for full caliber training and practice. And the Mark I in the backyard, garage, and basement."

I finally got rid of my arched MSHs (on all but historical or sentimental M1911s). But it really didn't make any difference and I could pick up and shoot either style easily.

This is my (former) Loaded model with a flat MSH (probably an Ed Brown Kobra checkered), proper trigger, thin AlumaGrips, removal of right side frame safety. USGI recoil spring, guide and plug. EGW barrel bushing. It probably had Ed Brown extractor, sear, and disconnector as well, but it's been a couple of years. I regret trading it. My Mark remains a good trainer.

As I noted earlier: "I swore for years I needed the arched mainspring housing in the M1911 and retrofitted it to all my M1911s. I'm down to 4 or 5 M1911s (yes, it's a disease but I'm recovering slowly...) with a mix of arched, straight, and bob-tailed MSHs and it doesn't seem to matter. I normally carry my Ed Brown Kobra Carry or Colt Commander and use a Government Model for full caliber training and practice. And the Mark I in the backyard, garage, and basement."

I finally got rid of my arched MSHs (on all but historical or sentimental M1911s). But it really didn't make any difference and I could pick up and shoot either style easily.

This is my (former) Loaded model with a flat MSH (probably an Ed Brown Kobra checkered), proper trigger, thin AlumaGrips, removal of right side frame safety. USGI recoil spring, guide and plug. EGW barrel bushing. It probably had Ed Brown extractor, sear, and disconnector as well, but it's been a couple of years. I regret trading it. My Mark remains a good trainer.

Sure. Cartridge or airsoft? I usually travel 30 miles to shoot cartridge guns outdoors as the local ranges suck. The reason I got into airsoft is a direct result of that driving requirement and my desire for more trigger time.

Sure. Cartridge or airsoft? I usually travel 30 miles to shoot cartridge guns outdoors as the local ranges suck. The reason I got into airsoft is a direct result of that driving requirement and my desire for more trigger time.

-- Chuck

Cartridge of course. I have plenty of land for airsoft but in NJ you need to be a in the military, a cop, or a crook to fore a gun! I'll buy the ammo, lol.